package Text0511;

public class Main {
    public static void main(String[] args) {
        MidStudent s1 = new MidStudent();
        s1.setIN("A",1,"AA");
        Student s2 = s1;
        s2.show();
        //MidStudent s3 = s2;
        MidStudent s4 = (MidStudent) s2;
        s4.show();
        //UNStudent s5 = s2;
        s4.showStatic();
        s4.changeSta();
        ((MidStudent) s2).setINAll("B",2,"BB",100);
        ((MidStudent) s2).showAll();
        s1.showIDNumber();
    }
}
